The invention relates to easy opening, self-contained, easy to use dispenser packages capable of economical, high-speed production, manufactured from a broad range of materials, many of which are recyclable.
The universal use of pouch style packages for a broad spectrum of products ranging from ketchup and other condiments to health and beauty aids as well as medical products in addition to various other foods and technical products is well known. Until the present they have been made of foil/plastic laminates. The underlying invention of the parent application is a pouch that instantly opens when the flap is raised. In a preferred embodiment it may be made of coextruded plastics comprised of as many as seven layers with a total thickness of about 0.0025xe2x80x3 to 0.003xe2x80x3. These layers typically must have very specific properties including oxygen barriers, moisture barriers, varying sealing and/or softening temperatures and printable surfaces. These films are typically delivered in large diameter rolls.
It has been further unexpectedly discovered that the walls of these pouches, even those containing a layer of foil all within the total thickness of about 0.0025xe2x80x3 to 0.003xe2x80x3 can be made with preformed bulges thus lowering costs in the range of about 20% to 30%. As an ancillary benefit the bulges eliminate wrinkles in the walls of the pouches.
This application is a continuation-in-part (CIP) of my earlier U.S. application Ser. No. 09/717,449, filed Nov. 20, 2000, entitled xe2x80x9cRECLOSABLE DISPENSER PACKAGE, RECLOSABLE OUTLET FORMING STRUCTURE AND METHOD AND APPARATUS FOR MAKING SAMExe2x80x9d, in which I claim an easy opening pouch or other type containment package wherein a flap member, either integral to the package or independently made and integrated with the package, is folded or hinged over and sealingly attached to cover one of a number of apertures or aperture forming structures, e.g., a hole, a cut pattern, a breakaway tip and/or a score pattern, whereby raising said flap member creates or uncovers an aperture in the wall of the containment package.
One of the major problems in the development of the coextrusions of plastic for the subject pouches is that the flap, when folded over and sealed to the outer surface of the pouch, needs to be sealed without inadvertently sealing together the inner surfaces of the pouch. If the inner surfaces are inadvertently sealed together at the wrong locations they could obstruct the outflow of the product. (As disclosed in U.S. application Ser. No. 09/717,449, where desired, highly controlled and precisely located seal patterns that selectively seal together portions of the inner surfaces of the pouch can be used to create a specific flow path inside of the pouch to control the rate of flow from the outlet of the contained product and to act as a valve.)
In accordance with certain embodiments of the invention, the flap surface layer which folds over and seals to the outer surface of the pouch is made of a material which seals at a significantly lower temperature than the plastic film layer of the inner wall surfaces which must be sealed together to create the edge seals. This avoids inadvertent sealing together of the inner wall surfaces when the flap surface layer is folded over and sealed.
In accordance with further embodiments of the invention, a third component layer of the multilayer film is provided which will not lose strength at substantially higher temperatures than the sealing temperatures used to seal together the inner wall surfaces of the plastic film layer to create the edge seals. This is necessary because the film of the pouches must retain its tensile strength in order to be pulled through the machine that makes the pouches, generally by draw-rollers. This tension force is significant, particularly on the cross edge seals which are at right angles (90xc2x0) to the direction of draw. If the seals are weakened or softened while still at the edge sealing temperature, they would stretch and/or pull apart, and the machine could not function properly.
Referring now specifically to the pouch style packages claimed in my underlying U.S. application Ser. No. 09/717,449, in these easy opening pouches, the flap member should not contain any product. This is because product in the flap member could adversely affect the ability of the flap to seal to the outer surface of the pouch, because the product in the flap could cool the film of the flap, thereby not allowing heat to seal it. Thus, the fill level of the pouch should be below the lowest line of the flap. In addition, in those versions where the flap covers a hole or cut pattern, the product, if filled too high, could or would flow or spill out of the hole or cut pattern and contaminate the flap seal. Old style foil based packages not having such a flap do not have this restriction and are generally shorter than the easy opening pouches of U.S. application Ser. No. 09/717,449.
Although the material cost of the all-plastic versions the pouches of U.S. application Ser. No. 09/717,449 is significantly lower than the cost of the foil based old style packages, if the material cost differential from the old style packages could be increased it would be a great improvement. In addition it is axiomatic that all pouches made of flat material must wrinkle when being made simply because they have flat edge seals yet the containment walls must be contoured to encompass the product contained; curved surfaces intersecting with flat surfaces must create wrinkles. It occurred to me that if I could pre-form a bulge pocket formation in the containment walls I could eliminate the wrinkles and reduce the overall material required to contain the same amount of product, thereby greatly reducing the cost of the pouch. I had, however, doubts about forming such thin film of about two and a half thousandths of an inch in thickness (0.0025xe2x80x3-0.003xe2x80x3). I ran some tests and got very unexpected results. I was able to form a bulge in a wall without overly reducing the wall thickness (and therefore without overly reducing barrier qualities). Actually, packages in accordance with this invention have been produced with such bulges in one side only that have resulted in increasing the volume contained by as much as 40% and bringing the material cost down so low that it costs only about ⅓ that of an old style pouch made with a foil layer.
On another subject, as previously mentioned, the wide use of aluminum foil/plastic laminates for the production of old style pouch packages with no flap for a broad spectrum of products ranging from ketchup and other condiments to health and beauty aids as well as medical products, and all sorts of other food and technical products, such as glues, epoxies, etc., etc., is well known. They are generally made of combinations of very thin layers laminated together to an overall thickness total of about 0.003xe2x80x3 (three thousands of an inch). These materials are made into rolls of flat material. These rolls of flat material are then mounted on high-speed pouch making machines, which are utilized to produce the pouches. Since pouches are not flat, it is necessary that they wrinkle at the seals and various of their other surfaces, and it has been generally assumed that these very thin aluminum foil layers used in the laminations generally of a thickness of two to three ten thousandths of an inch (0.0002xe2x80x3-0.0003xe2x80x3) cannot be formed without rupturing. It has been unexpectedly discovered that the material used to form these aluminum foil based pouches does allow for some minimum forming and can be formed with slightly bulging formations, on at least one and in some cases both of their side walls. These formations allow for significantly greater containment volume and tend to eliminate seal wrinkles, since, as above-mentioned, the aluminum does stretch to a slight degree. This additionally means that there can be significantly less material used to contain the same quantity of product even in these aluminum foil based pouches, in the range often (10) to thirty (30) percent.
It will be appreciated by those skilled in the art that the forgoing various brief descriptions and the following detailed descriptions are exemplary and explanatory of the present invention, but are not intended to be restrictive thereof or limiting of the advantages which can be achieved by the invention or various combinations thereof. The accompanying drawings, referred to herein and constituting a part hereof, illustrate preferred embodiments of the invention and, together with the detailed description, serve to explain the principles of the invention.